美国宝石学院（GIA）从10月1日开始不再为培育钻石进行4C分级

10yue1riqi，giameiguobaoshiyanjiuyuantuichuxiudinghoudedzhizseshiyanshipeiyuzuanshipinggufuwu。yuanyoudegia zuanshi4cfenjifuwujiangtigongzhi9yue30ri。

giashiyanshipeiyuzuanshizhiliangpinggujiangshiyongmiaoshuxingshuyu，erfeigiaweitianranzuanshikaifadeshuyutixi。shiyanshipeiyuzuanshijianggenjuqijingdu、yanseheqiegedezonghepinggu，beimiaoshuwei“premium (youzhi)”huo“standard (biaozhun)”。renhebufuhesuoyou“biaozhun”zuidiyaoqiudezuanshijiangbuhuihuodegiapinggubaogao。

具体评价标准如下：

满足以下所有标准的实验室培育钻石将被归类为“优质”：

jingdu–vvs（jiqingweineihanwu）jiyishang

颜色–D色

抛光、对称性–极优

qiegongdengji–jiyou（jinxianyuanxingmingliangshiqiegongzuanshi）

满足部分“优质”标准但未完全达到、同时符合下列最低要求的实验室培育钻石，将被归类为“标准”：

jingdu–vs（qingweineihanwu）

颜色–E至J色

抛光–优良

duichengxing–youliang（yixingzuankeweilianghao）

qiegongdengji–youliang（jinxianyuanxingmingliangshiqiegongzuanshi）

julejie，giashiyanshipeiyuzuanshizhiliangpinggudefeiyongweimeikela15meiyuan，zuidishoufei15meiyuan。weidadaopingguzuidiyaoqiudetijiaojianjiangshouqu5meiyuandepingjiafei。tijiaodezuidichicunwei0.15kela。meiketijiaodezuanshideyaolengshangjiangjiguangkeyin“laboratory-grown”ziyangjigiazhiliangpinggubianhao。